Civil Engineering March 2021 | Vol 29 No 2

74 March 2021 Civil Engineering Ob i tuary Johan Albert (Joop) Zwamborn, one of the “founding fathers” of coastal and port engineering in South Africa, died on 13 January 2021 at the age of 89. He was particularly well-known for his scientific work on the Dolos armour unit which led to its widespread use as the primary armour unit on hundreds of breakwaters and shore-protection works across the globe. EARLY LIFE AND CAREER After graduating from the Delft University of Technology, Joop and his wife Hennie emigrated to South Africa from the Netherlands in 1955, when he was 24. He initially worked on bridge construction for two years as an engineer at the South African Railways and Harbours Administration. Thereafter, he joined the Benoni Municipality for two years as a hydraulics engineer, where he compiled a design manual for stormwater drainage systems. Joop then joined the Council for Scientific and Industrial Research (CSIR), where he served as a hydraulic and coastal research engineer and manager for more than three decades, from 1959 to 1992. After his retirement in 1992, he continued working for a further 25 years as a specialist consultant in port engineering. Joop’s career at the CSIR started in Pretoria, where he worked with Dr Jan Jordaan on model studies for the improve- ment of the eroding Durban main beach. He compiled a widely used manual on scaling laws for sediment dynamics. In 1961/62, he went back to Delft to study coastal engineering at the International Centre for Hydraulic Engineering (now IHE Delft Institute for Water Education). Joop moved to Stellenbosch with his wife and daughters in 1968 when the CSIR decided to build a hydraulics laboratory in Stellenbosch. Heading the new group, he was responsible for the design and construction supervision of the new laboratory with a floor area of 12 000 m 2 , including water-circulation systems, wave generation, and measuring equipment. This facility remains the largest coastal and hydraulics laboratory in the Southern Hemisphere. Joop was an active member of SAICE, the International Association of Hydraulics Research, and the World Association for Waterborne Transport Infrastructure. His main contributions and efforts were in coastal and port engineering. CAREER ACHIEVEMENTS Joop commenced the scientific evaluation, testing, and improvement of the Dolos armour unit for breakwaters in 1965, after its invention by Eric Merrifield, a harbour engineer at East London. This led to a systematic series of tests of this unit and its application in projects, which lasted decades. His research publications led to the international application of the Dolos in many breakwaters around the world. In the field of breakwater armour design, he built strong ties with the US Army Corps of Engineers’ Coastal Engineering Research Center and other laboratories. This also led to his participation in inter- national working groups and the review of Dolos armour unit applications, including an assessment of the failure at the Port of Sines in Portugal and a review of the Gioia Tauro breakwater in Italy (1978 to 1982). For the development of the Port of Richards Bay (1969 to 1976), Joop man- aged a series of model studies critical to the design of the port. These included studies on the breakwater design (layout and detail), wave refraction and wave penetration in the entrance channel, port entrance channel layout, and vertical ship In Memoriam: Joop Zwamborn Joop Zwamborn at the Dolos stockpile at Lamberts Bay